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rebuilding, controller will start the above Auto-Rebuild process as
well. Auto-Rebuild feature only works at that the status of VG is
"Online"
. It will not work at
“Offline”
. Thus, it will not conflict with
the
“Roaming”
.
3. In degraded mode, the status of VG is “Degraded”. When rebuilding,
the status of VG/UDV will be “Rebuild”, the column “R%” in UDV will
display the ratio in percentage. After complete rebuilding, the status
will become “Online”. VG will become completely one.
Sometimes, rebuild is called recover; they are the same meaning. The
following table is the relationship between RAID levels and rebuild.
RAID 0
Disk striping. No protection for data. VG fails if any hard drive
fails or unplugs.
RAID 1
Disk mirroring over 2 disks. RAID 1 allows one hard drive fails
or unplugging. Need one new hard drive to insert to the
system and rebuild to be completed.
N-way
mirror
Extension to RAID 1 level. It has N copies of the disk. N-way
mirror allows N-1 hard drives failure or unplugging.
RAID 3
Striping with parity on the dedicated disk. RAID 3 allows one
hard drive failure or unplugging.
RAID 5
Striping with interspersed parity over the member disks. RAID
5 allows one hard drive failure or unplugging.
RAID 6
2-dimensional parity protection over the member disks. RAID
Tips
“Set dedicated spare”
is not available if there is no VG or
only VG of RAID 0, JBOD, because user can not set dedicated
